All the poop here:
https://www.gov.uk/importing-vehicles-into-the-uk/overviewSee section 3, Paying VAT and duty, about importing second-hand.
Think you might be screwed tho, one of the conditions for avoidung VAT is that the vehicle has done > 6,000 km, and 3,400 miles does not quite make it. Might be able to swing it tho on the basis of it being 2012. But will need to ask them.